Spearman's theory that all mental abilities draw from a single capacity.

Spearman focused on studying the mental ability of children. [ He formed a theory based on his study that there were two factors of measure for intelligence.The first part of the two factor theory is general intelligence factor, otherwise labeled as "g". Spearman's theory showed that all aspects of intelligence correlate with each other and are controlled by "g". General intelligence factor

overlaps all other more specific intelligence factors.The second part of the two factor theory is specific intelligence factor, otherwise labeled as "s". Specific intelligence factors are specific to a single activity. These areas do not necessarily overlap or share much correlations to each other. The "s" factors are all overlapped and joined together by the primary "g" factor.The difference between "s" and "g" factors is the amount of correlations. A "g" factor has a correlation between at least two mental functions while an "s" factor mostly corresponds to only a single mental function. "S" factors are specialized and may not be a perfect measure of intelligence level. Instead the two factor theory claims that "g" factors are the way to test intelligence level of an individual. It rules out specialization of the individual towards a specific mental function and attempts to instead measure the entire mental capacity. "S" factors on the other hand only show how intelligent the individual is in a specific mental function. A person could potentially be very intelligent in one mental function area but score very low in a different one. By judging "g" factors instead the test would instead overlap multiple mental function areas and thus come up with a more generalized measure of the whole mind. More reference links: sitemaker.umich.edu human-nature.com
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